Airtight zipper construction

ABSTRACT

An airtight zipper construction is provided that can be installed on any bag body and seals the bag completely. The airtight zipper construction comprises a first zipper tape having a first zipper groove, a second zipper tape having a sealing portion at its end and a second zipper groove engaged with the first zipper groove, and a first slide with a separating portion. The separating portion divides the inner chamber of the slide into an upper guiding passage and a lower guiding passage. The first zipper tape and the second zipper tape are inserted through the upper guiding passage and the lower guiding passage, respectively. The first zipper tape is engaged into the second zipper tape from zipper head toward zipper end, with the first zipper tape covering the second zipper tape, and the first slide jammed into the sealing portion without any gaps.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a zipper construction, and in particular to an airtight zipper construction which may be mounted on any bag body and prevent the gas or liquid contained in the bag body from leaking out.

2. The Prior Arts

Please refer to FIG. 1, which illustrates the construction of a zipper installed on a storage bag according to the prior art. The storage bag comprises mainly a bag body 10 and a zipper 20. Zipper 20 interlocks and closes bag 20 from zipper head 201 toward zipper end 202. Please refer to FIG. 2A, which illustrates the zipper end 202 of zipper 20, wherein zipper 20 comprises two zipper tapes 21, two closing units 22 and one zipper slide 23. The two zipper tapes 21 are interlocked or separated by pulling zipper slide 23. When interlocked, the upper and lower zipper grooves 211 are engaged downward and upward respectively with each other by pulling the pull tab 233. Each end of the two zipper tapes 21 comprises a closing unit respectively, which is generally installed by heat-sealing and functions as an end stopper for zipper slide 23 as well as a joint between zipper 20 and bag body 10.

Please refer to FIG. 2A and FIG. 2B simultaneously. It is disclosed that when the zipper slide 23 is pulled to the zipper end 202, a gap is inevitably formed in front of the zipper slide 23. The gap makes it impossible to completely seal the bag body 10 and causes the gas or liquid contained in the bag to pass through the gap. Moreover, another gap is formed between the lower guiding passage 232 of the zipper slide 23 and the lower zipper tape 21. This gap is connected with the upper guiding passage 231 and leads to the outside of the bag body 10, which makes it impossible for the bag body 10 to be completely sealed and obtain airtight effect.

In another aspect, when said zipper slide 23 is pulled to the zipper end 202, there is no component or device to fasten the zipper slide 23, so that when the bag body 10 is in use or in storage, the zipper slide 23 may readily slide in the reversed direction and unseals the bag body. Moreover, when zipper tape 21 and zipper groove 211 are over-bent, the two zipper grooves 211 may easily disengage from each other. Therefore when storing or using a storage bag with a zipper of the prior art, it is not easy to keep the bag body 10 closed, not to mention to obtain airtight effect.

SUMMARY OF THE INVENTION

To entirely seal the gap formed after the bag body is zipped, to prevent the zipper slide from coming loose or sliding away when the bag is in use or in storage, as well as to reduce the possibility of zipper grooves disengaging from each other when the zipper tape and zipper groove are over-bent, an airtight zipper construction will be provided in the present invention, which eliminates gaps after the zipper is closed to obtain completely airtight effect, at the same time fastens the zipper slide when it is pulled to position to prevent it from sliding away by accident, and insures the engagement of zipper grooves by preventing the zipper tapes and zipper grooves from getting over-bent.

According to the present invention, the airtight zipper construction comprises a first zipper tape having a first zipper groove; a second zipper tape having a second zipper groove reciprocally engaged into the first zipper groove and a sealing unit near the zipper end; and a first zipper slide having a pull tab and a separating portion therein. Said separating portion divides the inner chamber of the said first zipper slide into an upper guiding passage and a lower guiding passage, wherein said first zipper tape is inserted through the upper guiding passage, and is engaged from zipper head toward zipper end into the second zipper tape, which is in turn inserted through said lower guiding passage, with said first zipper tape interlocking and covering over said second zipper tape, and said first zipper slide inserted and jammed into said sealing unit without any gaps. Said first zipper groove of said first zipper tape is adjoined to a side wall of said upper guiding passage. Inside said sealing unit a reversed L-shaped opening is formed, which extends horizontally from said second zipper groove at the edge of said second zipper tape toward the inside of said second zipper tape, then extends longitudinally toward the head of the zipper. Said sealing unit may also be disposed on said first zipper groove, with its opening extending horizontally from the first zipper groove at the edge of said first zipper tape toward the inside of said first zipper tape, then extending longitudinally toward the head of the zipper.

In another aspect, a reversed U-shaped first jamming pad may be further mounted on the surface of said first zipper tape and said second zipper tape where said sealing portion in installed, wherein the U-shaped opening of said first jamming pad opens to the head or the zipper, and the inner rim of the opening is formed along the edges of said first zipper groove and said second zipper groove. Besides, A second jamming pad may be installed alone or simultaneously on the surface of said first zipper tape and said second zipper tape where said sealing unit is installed, wherein the U-shaped opening of said second jamming pad opens to the head of the zipper and the inner rim of the opening is formed along the edges of said first zipper groove and said second zipper groove.

By the installation of the sealing unit of the present invention, the right flank of the first zipper slide may be directly inserted and jammed into said sealing unit, so that the front of the first zipper slide is embedded under the zipper tape, which eliminates the gap existing between the upper and lower zipper tapes and enables a completely airtight effect for the present invention. On the other hand, because of the disposition of the jamming pad, the thickness of the first zipper tape and the second zipper tape, which are inserted through the upper guiding passage and the lower guiding passage respectively, increases, so that when the first zipper slide is pulled passing said zipper tape segment near the sealing unit, it is squeezed and fastened to the zipper tape, and may not slide backward easily. The jamming pad squeezes the first slide toward the center and presses the first zipper slide and zipper tapes closer together without any gaps.

According to in the present invention, an insulating pad may be further mounted below the surface of said first zipper tape and said second zipper tape where said sealing unit is installed. An opening in formed at the side of the insolating pad facing the zipper head, so that said zipper slide may slide over the insolating pad and interlock toward said sealing unit. The other three sides of the insolating pad are tightly attached on said first zipper tape and said second zipper tape. The installation of the insolating pad decreases the possibility for the gas and liquid to enter the sealing unit, increases the sealing effect of said sealing unit, and protects the L-shaped opening from being torn apart by external force. Furthermore, according to the present invention, to prevent the zipper tapes and zipper grooves from being over-bent and consequently disengaging the upper zipper groove from lower zipper grooves, a reinforcing rib may be mounted on the first zipper tape and/or second zipper tape to increase the thickness thereof, and maintains the airtight status of the bag body.

The preferred embodiment of the present invention will be described in more detail with reference to the accompanying drawings. It should be appreciated that any embodiment described below is intended to illustrate the present invention, not to limit its scope. Variations may be made thereto without departing from the spirit and scope of the present invention by people skilled in the pertinent art. The true scope of the invention is set forth in the claims appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a prior art storage bag.

FIG. 2A is a schematic view of a prior art storage bag zipper.

FIG. 2B is a side, schematic view of a prior art storage bag zipper.

FIG. 3A is a schematic view of a zipper according to a preferred embodiment of the present invention.

FIG. 3B is a schematic view of a first zipper slide used in the preferred embodiment of the present invention.

FIG. 4A is a schematic view of a zipper groove according to the preferred embodiment of the present invention.

FIG. 4B is a schematic view of a first zipper groove inserted through an upper guiding passage according to the preferred embodiment of the present invention.

FIG. 5A is a side, schematic view of a first zipper slide before it is pulled to the sealing unit according to the preferred embodiment of the present invention.

FIG. 5B is a side, schematic view showing a first zipper slide jammed into a sealing unit according to the preferred embodiment of the present invention.

FIG. 5C is a side, schematic view of another sealing unit and the first zipper slide according to the preferred embodiment of the present invention.

FIG. 5D is a side, schematic view of the first zipper slide jammed to the sealing unit according to the preferred embodiment of the present invention.

FIG. 6A is a schematic view of a first jamming pad according to the preferred embodiment of the present invention.

FIG. 6B is a schematic view showing the first zipper slide being pulled onto the first jamming pad.

FIG. 7 is a schematic view of a second jamming pad according to the preferred embodiment of the present invention.

FIG. 8A is a schematic view of an insulating layer according to the preferred embodiment of the present invention.

FIG. 8B is a side, schematic view showing the installation of the insulating layer according to the preferred embodiment of the present invention.

FIG. 8C is a schematic view of a covering layer according to the preferred embodiment of the present invention.

FIG. 9A is a schematic view of reinforcing ribs of the preferred embodiment of the present invention.

FIG. 9B is a cross-sectional, schematic view of the preferred embodiment of the present invention.

FIG. 9C is a schematic view of a second preferred embodiment of the reinforcing ribs according to the present invention.

FIG. 9D is a schematic view of a third preferred embodiment of the reinforcing ribs according to the present invention.

FIG. 9E is a schematic view showing the reinforcing, ribs on a bag body according to the preferred embodiment of the present invention.

FIG. 10 is a schematic view showing the arrangement of a second embodiment of the first zipper slide according to the present invention.

FIG. 11 is a schematic view of a second embodiment of a bag body according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 3A, which is a schematic view of a zipper according to the preferred embodiment of the present invention, the zipper 30 comprises a first zipper tape 31, a second zipper tape 32, two sealing units 33, (only one of them is shown in the figure) and a first zipper slide 34. The first zipper tape 31 and second zipper tape 32 are interlocked by the first zipper slide 34 to be in engaged closed condition. The first zipper slide 34 is inserted into the sealing unit 322 from the front of the right flank 343, so that the zipper 30 is a sealed and interlocked construction.

Referring to FIG. 3B, the first zipper slide 34 comprises a separating portion 340, a lower guiding passage 342, a right flank 343, a slide base 344, and a pull tab 345. The separating portion 340 divides the first zipper slide 34 into an upper chamber and a lower chamber as upper guiding passage 341 and lower guiding passage 342 respectively. The wall to the right of the upper guiding passage 341 is the right flank 343, whose width is W1, whereas the length from the front of the first zipper slide 34 to the end of the separating portion 340 is L1. Please refer to FIG. 4A for the assembly arrangement of the first slide 34 and both zipper tapes. A first zipper groove 311 of the first zipper tape 31 is inserted through the upper guiding passage 341 of the slide 34, whereas a second zipper groove 321 of the second zipper tape 32 is inserted through said lower guiding passage 342. The jamming force and separating force between the upper guiding passage 341, lower guiding passage 342 and the separating portion 340 interlock or separate the first zipper tape 31 and second zipper tape 32. When the first zipper groove 311 is interlocked with the second zipper groove 321, the grooves thereof reciprocally engage into each other like an airtight sealant. There is no limit to the number of grooves disposed on the first zipper groove 311 and second zipper groove 321. The number may be one, two, three, four, or more. The width of the first zipper slide 34 depends on the number of grooves. Increasing the number of grooves may enhance the strength of interlocking without increasing the thickness of the zipper grooves.

Referring to FIG. 3A, FIG. 3B and FIG. 4 simultaneously, according to the preferred embodiment of the present invention, a sealing unit 322 is installed on the second zipper tape 32. Said sealing unit 322 may be disposed near the front of zipper end 301. The sealing unit 322 comprises an opening 3221 and a protruding flap 3222. The opening 3221 is substantially reversed L-shaped, extending horizontally from the second zipper groove 321 at the edge of the second zipper tape 32 to the inside of the second zipper tape 32 and defining a width W3, then extending longitudinally toward zipper head (not shown in the Figure) and defining a length L2. The transverse width W3 of the opening 3221 may be slightly smaller than the sum of the width W2 of the second zipper groove 321 plus the width of the right flank 343, whereas its longitudinal length L2 may be lightly smaller than the length L1 from the front of the first slide 34 to the end of the separating portion 340. The segment cut by the opening 3221 on the second zipper tape 32 is a protruding flap 3222. The second zipper tape 32 may be interlocked from the opening 3221 to the zipper end 301 with the corresponding portion of the first zipper tape first, thus a sealing hole 60 is formed at the sealing unit 322. The width W3 and the longitudinal length L2 of the opening 3221 are not limited by the description above, and are subject to modification according to the size of the zipper slide. Besides, referring to FIG. 4B, the first zipper groove 311 of the first zipper tape 31 is adjoined to the side wall of the upper guiding passage 341, so that the space in the upper guiding passage below the first zipper tape 31 is isolated from the outside after the zipper is interlocked, which prevents the gas or liquid below the first zipper tape (that is, inside the bag body) from leaking upward from the gap between the first zipper groove 311 and the side wall of the upper guiding passage 341. According to the prior art, a gap is formed between the side wall of the upper guiding passage and the zipper tape. In the present invention, the thickness of the side flap of the first zipper groove 311 may be increased so that the flap may be adjoined with the side wall of the upper guiding passage 341, or an extending flap may be added during the fabrication of the first zipper groove 311 (not shown in the figure) so that the same adjoining and isolating effect is achieved.

Please refer to FIG. 5A, which, according to the preferred embodiment of the present invention, is a side schematic view of the first slide before it is pulled to the sealing unit. It is also a side view of FIG. 4. The protruding flap 3222 is formed cut out from the second zipper groove 321 of the second zipper tape 32. After the cut, the support at the opening of the second zipper tape 32 disappears, and the protruding flap which is extended from the lower guiding passage 342 hangs down at a certain angle. The aforementioned sealing hole 60 is thus formed between the hanging protruding flap 3222 and the first zipper tape 31.

Please refer to FIG. 5A and FIG. 5B simultaneously. FIG. 5B is a side schematic view of the zipper slide jammed into the sealing unit according to the preferred embodiment of the present invention. When the first slide 34 was further pulled toward said sealing unit 322, the right flank 343 of the first slide 34 will move into said sealing hole 60 in accordance, so that the whole front portion of the first slide 34 will be embedded in the second zipper tape 32 completely, which eliminates the original gap existing between the prior art zipper grooves 211, (please refer to FIG. 2) and seals the sealing hole 60 defined by the L-shaped opening 3221. Besides, after the first zipper slide 34 is inserted into the sealing hole 60, the original gap between the second zipper tape 32 and the lower guiding passage 342 may no longer lead to the upper guiding passage 341; moreover, the first zipper groove 311 of the first zipper tape 31 is adjoined to the side wall of the upper guiding passage, which blocks the gas or liquid in said first zipper groove 311 and the upper guiding passage 341 from leaking out. On the other hand, the original front opening and side opening of the lower guiding passage 342 is also embedded in the sealing hold 60 in accordance with the insertion of the first slide 34, which enables the zipper of the present invention to obtain a completely airtight effect.

Besides, to increase the tightness between the first slide 34 and zipper tapes, the width of the opening 3221 may be slightly smaller than the width W2 of the second zipper groove 321 plus the width W1 of the right flank 343, so that when the right flank 343 is moved into the sealing hole 60, the second zipper tape 32 may squeeze the right flank 343 toward the center to eliminate the gap between the right flank 343 and the second zipper 32, and to insure the tightness between them.

Please refer simultaneously to FIG. 5C and FIG. 5D, which, according to the preferred embodiment of the present invention, are side schematic views showing the zipper slide jammed to another sealing unit. Besides disposing a sealing unit 322 on the second zipper tape 21 as described above, another opening 3121 symmetric to the aforementioned opening 3221 may be formed on the first zipper tape 31. When the opening 3121 is cut out on the first zipper tape 31, a protruding flap 3122 is formed. The opening 3121 and the protruding flap 3122 constitute a sealing unit 312 in another form and a sealing hole 61, into which the first zipper slide 34 may be inserted. When the first slide 34 is inserted into the sealing hole 61, it is not embedded downwardly as is in the aforementioned preferred embodiment (please refer to FIG. 5B), but retains its original elevation and moves through the sealing hole 61, causing the first zipper tape 31 adjacent to the opening 3121 to tightly cover the left flank of the zipper slide 34, and constituting a completely sealed construction in equality.

Please refer to FIG. 6A and FIG. 6B simultaneously, which are schematic views of jamming pads according to the preferred embodiment of the present invention. To prevent the first slide 34 from sliding backward after it is pulled to the sealing unit 322 when the bag body is in use, a reversed U-shaped first jamming pad 40 may be further mounted on the surface of the first zipper tape 31 and the second zipper tape 32 where the sealing unit is installed. The inner rim of the reversed U-shaped opening of said first jamming pad 40 is formed along the edges of the first zipper groove 311 and the second zipper groove 321, and covers the area from in front of the sealing unit 322 to in its back. The first jamming pad thickens the area of the first zipper tape 31 and the second zipper tape 32 from in front of the sealing unit 322 to in its back, so that when the first slide 34 is pulled through said area, the additional thickness of the first zipper tape 31 and the second zipper tape 32 jams the upper guiding passage 341 and lower guiding passage 342 respectively. In this way, when pulled to the sealing unit 322, the first slide 34 may be fixed in the sealing unit 322 by the first jamming pad. This prevents the first slide 34 from sliding backward by accident and influencing the airtight effect. Besides, a first concave slanting opening 41, which slants toward the first zipper groove 311 and second zipper groove 321 respectively, may be formed at the jamming pad 40 near the zipper head between the two legs of the reversed U-shape, so that the first slide 34 may move more smoothly along said concave opening when it is pulled toward the sealing unit 322. In addition to the aforementioned application, the installation of first jamming pad may further strengthen the opening 3221, so that the opening 3221 may not tear when it is pulled with a great force. Furthermore, the installation of the first jamming pad 40 helps the second zipper tape 32 to squeeze the first slide 34 inward, so that the right flank 343 is adjoined to the first zipper groove 311 more tightly, and the second zipper tape 32 covers the right flank 343 of the first zipper slide 34 more closely. In sum, the first jamming pad 40 not only provides the jamming function, but also reinforces the tightness of the zipper slide 34 insertion.

Referring to FIG. 7, besides the first jamming pad 40, which is installed on the surface of the sealing unit 322, a second jamming pad 50 may be installed alone or simultaneously below the surface. The second jamming pad 50 is also reversed U-shaped with a second concave slanting opening 51. The only difference that differentiates it from the first jamming pad 40 is that it is installed below the surface of the first zipper tape 31 and the second zipper tape 32. Its function and effect are the same as those of the first jamming pad 40.

Please refer to FIGS. 8A and 8B simultaneously which are schematic views of an insulating layer according to the preferred embodiment of the present invention. To further reinforce the airtight effect, an insulating layer 70 may be further mounted below the surface of the first zipper tape 31 and the second zipper tape 32 where the sealing unit 322 is installed. Said insulating layer 70 has an opening 71 at the side facing toward the zipper head, so that the first zipper slide 34 may slide through and interlock toward said sealing unit 322. The other three sides of the insulating layer are tightly attached on the first zipper tape 31 and the second zipper tape 32 to further reinforce the airtight effect of the zipper and protect the opening 3221 from tearing because of outer force.

Please refer to FIG. 8C, which is a schematic view of a covering layer according to a preferred embodiment of the present invention. To cover the opening of the upper guiding passage 341 of the first zipper slide 34 after the first zipper slide 34 is pulled to position and to increase exquisiteness, a covering layer 80 may be mounted next to the sealing unit 312 on the surface of the first zipper tape 31 and the second zipper tape 32 according to the present invention. The covering layer 80 is similar to separating layer 70 in structure. It also has an opening 81 where the first zipper slide may be inserted into the covering layer 80 after it is pulled to the sealing unit 322. The covering layer 80 may be mounted alone or with the insulating layer 70 simultaneously. It should be noted that the length of the covering layer 80 depends on the position where the pull tab 345 of the first zipper slide 34 may be pulled. If it is too long, the first zipper slide 34 may not be inserted into the sealing unit completely.

Please refer to FIG. 9A to FIG. 9D, which are schematic views of zippers according to the preferred embodiment of the present invention. To prevent the zipper grooves from disengaging with each when the zipper tapes and the zipper grooves are over-bent, a first reinforcing rib 313 and a second reinforcing rib 323 may be mounted on the first zipper tape 31 and the second zipper tape 32 to increase their thickness. After the reinforcing ribs are mounted, the zipper grooves thicken so that they may only be slightly curved, but may not be bent, which effectively prevents the zipper grooves from disengaging and retains the airtight condition of the bag body. In the preferred embodiment, the first reinforcing rib 313 and the second reinforcing rib 323 are slab-like bulging matter, but their shape, mounting method and position are not limited to the description above. Besides being formed during fabrication to increase the thickness, the reinforcing rib 313 may be stuck to the zipper tapes as an attachment. It can be mounted on the surface of the zipper tape, below the surface of the zipper tape, or both. Once the reinforcing rib 313 is mounted, the zipper 30 may be rolled up for storage with the surface on which the reinforcing rib 313 is mounted as its inner side to protect the zipper. Please refer to FIG. 9E. Besides increasing the thickness of the zipper tapes as described above, a reinforcing rib 11 may be mounted on the joint of the bag body 10 with the first zipper tape 31 or with the second zipper tape 32 to achieve the aforementioned effect.

Please refer to FIG. 10, which is a schematic view of a zipper slide according to a second preferred embodiment of the present invention to serve special purposes. For example, when a major disaster claims many lives, sometimes people who are alive but fainted are put into corpse bags by mistake. When they come to, they need to pull the zipper slide 34 to open the bag body 10 from its inside. To serve such need, a lower pull tab 347 is coupled to the slide base 344 of the zipper slide 34 at a position opposite to the pull tab 345, and constitutes a slide with twin pull tabs. The lower pull tab 347 should be mounted near the rear of the slide base 344, so as not to influence the airtight effect between the first zipper slide 34 and the sealing unit 322. Besides, a second sealing unit and a second zipper slide (not shown in the figure) which are structurally equivalent to the sealing unit 322 and the first zipper slide 34 may be further installed at the zipper head 201, with the second zipper slide inserted and jammed into said second sealing unit without any gaps, forming an airtight construction. Said second zipper slide is installed reversed and leftside right to the first zipper slide 34, with a lower pull tab (not shown in the figure) of the second zipper slide installed below the first zipper tape 31 and the second zipper tape 32 (inside the bag body 10) As it is difficult to turn the body around inside the bag, by pulling at the lower pull tab of the first zipper slide 34 or the second zipper slide from the zipper head 201 or the zipper end 202, the zipper may be opened from the inside, so that the same result as aforementioned is achieved.

Please refer to FIG. 11, which is a schematic view of the second preferred embodiment of the present invention. Once the zipper 30 is mounted on the bag body 10, to further prevent the two ends where the zipper 30 are joined to the bag body 10 from being pulled off or the bag body being torn apart accidentally by outer force, a reinforcing pad 12 may be further mounted on the bag body 10 where the zipper head 201 and the zipper end 202 are joined respectively, which reinforces the installation of the zipper 30 to the bag body 10, and covers the joints to obtain exquisiteness for the design. 

1. An airtight zipper construction comprising: a first zipper tape, said first zipper tape having a first zipper groove; a second zipper tape, said second zipper tape having a second zipper groove which is engaged into said first zipper groove, and a sealing unit near the end of the zipper; and a first zipper slide, said zipper slide having a pull tab and a separating portion therein, said separating portion dividing the inside chamber of said first zipper slide into an upper guiding passage and a lower guiding passage, wherein said first zipper tape is inserted through said upper guiding passage, said second zipper tape is inserted through said lower guiding passage, and said first zipper tape is interlocked with and covering over said second zipper tape from the head of the zipper toward the end, enabling said first zipper slide to be inserted and jammed into said sealing unit without any gaps.
 2. The airtight zipper construction as claimed in claim 1, wherein said sealing unit is a reversed L-shaped opening, said opening extending horizontally from said second zipper groove at the edge of said second zipper tape toward the inside of said second zipper tape, then extending longitudinally toward the zipper head.
 3. The airtight zipper construction as claimed in claim 1, wherein said first zipper groove of said first zipper tape is adjoined to a flank of said upper guiding passage.
 4. The airtight zipper construction as claimed in claim 1, wherein a reversed U-shaped first jamming pad is mounted on the surface of said first zipper tape and second zipper tape where said sealing unit is installed, said reversed U-shaped opening of said first jamming pad opening toward said zipper head, and the inner rim of said opening formed along the edges of said first zipper groove and said second zipper groove.
 5. The airtight zipper construction as claimed in claim 4, wherein a concave slanting opening is formed on said first jamming pad near the zipper head between the two legs of the reversed U-shape, said concave slanting opening slanting toward said first zipper groove and said second zipper groove respectively.
 6. The airtight zipper construction as claimed in claim 1, wherein a reversed U-shaped second jamming pad is mounted below the surface of said first zipper tape and said second zipper tape where said sealing unit is installed, the reversed U-shaped opening of said second jamming pad opening toward said zipper head, and the inner rim of said opening formed along the edges of said first zipper groove and said second zipper groove.
 7. The airtight zipper construction as claimed in claim 6, wherein a concave slanting opening is formed on said second jamming pad near the zipper head between the two legs of the reversed U-shape, said concave slanting opening slanting toward said first zipper groove and said second zipper groove respectively.
 8. The airtight zipper construction as claimed in claim 1, wherein an insulating layer is further mounted below the surface of said first zipper tape and said second zipper tape where said sealing unit is installed, said insulating layer having an opening at the side facing the zipper head, therethrough said first zipper slide may move and interlock toward said sealing unit, said insulating layer having the other three sides tightly attached to the zipper tape of said first zipper tape and said second zipper tape.
 9. The airtight zipper construction as claimed in claim 1, wherein a covering layer is further mounted on the surface of said first zipper tape and said second zipper tape where said sealing unit is installed, said covering layer having an opening at the side facing the zipper head, therethrough said first zipper slide may move and interlock toward said sealing unit, said covering layer having the other three sides tightly attached to the zipper tape of said first zipper tape and said second zipper tape.
 10. The airtight zipper construction as claimed in claim 1, wherein a first reinforcing rib is formed to thicken said first zipper tape.
 11. The airtight zipper construction as claimed in claim 1, wherein a second reinforcing rib is formed to thicken said second zipper tape.
 12. The airtight zipper construction as claimed in claim 1, wherein a lower pull tab is further mounted below said first zipper slide and opposite said pull tab.
 13. The airtight zipper construction as claimed in claim 1, wherein a second zipper slide and a second sealing unit are further mounted on said zipper head, said second zipper slide being reversed and leftside-right to said first zipper slide, thereon a second pull tab is mounted below said first zipper tape and second zipper tape, enabling said second zipper slide to be inserted and jammed into said second sealing unit.
 14. An airtight zipper construction comprising: a first zipper tape, said first zipper tape having a first zipper groove, and a sealing unit near the zipper end; a second zipper tape, said second zipper tape having a second zipper groove which is engaged into said first zipper groove; and a first zipper slide, said zipper slide having a pull tab and a separating portion therein, said separating portion dividing the inner chamber of said first zipper slide into an upper guiding passage and a lower guiding passage, wherein said first zipper tape is inserted through said upper guiding passage, said second zipper tape is inserted through said lower guiding passage, and said first zipper tape is interlocked with and covering over said second zipper tape from the head of the zipper toward the end, enabling said first zipper slide to be inserted and jammed into said sealing unit without any gaps.
 15. The airtight zipper construction as claimed in claim 14, wherein said sealing unit is a reversed L-shaped opening, extending horizontally from the first zipper groove at the edge of said first zipper tape toward the inside of said first zipper tape, then extending longitudinally toward the head of the zipper.
 16. The airtight zipper construction as claimed in claim 14, wherein said first zipper groove of said first zipper tape adjoins to a flank of said upper guiding passage.
 17. A bag body installed with the airtight zipper construction as claimed in claim 1, said bag body having reinforcing pads mounted where said zipper head and said zipper end of said airtight zipper join said bag body, respectively. 